Synthesis of Onychine and Formal Synthesis of Eupolauridine via the Vinylogous Aza-Morita-Baylis-Hillman Reaction

Abstract

A concise and efficient synthesis of the antimycotic alkaloid onychine was developed, based on the vinylogous aza-Morita-Baylis-Hillman reaction of N-(benzylidene)benzenesulfonamide with methyl 2,4-pentadienoate, followed by intramolecular conjugate addition, Friedel-Crafts acylation, methyl cuprate addition, and aromatization.

alkaloids - onychine - aza-Morita-Baylis-Hillman ­reaction - cyclization - cuprates

References and Notes

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For experimental procedures and characterization data for new compounds and the final product 1, see the Supporting Information.